package com.atguigu.gulimall.product.service.impl;

import com.atguigu.gulimall.product.service.CategoryBrandRelationService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.*;
import java.util.stream.Collectors;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.atguigu.common.utils.PageUtils;
import com.atguigu.common.utils.Query;

import com.atguigu.gulimall.product.dao.CategoryDao;
import com.atguigu.gulimall.product.entity.CategoryEntity;
import com.atguigu.gulimall.product.service.CategoryService;


@Service("categoryService")
public class CategoryServiceImpl extends ServiceImpl<CategoryDao, CategoryEntity> implements CategoryService {

    @Autowired
    CategoryBrandRelationService categoryBrandRelationService;

    @Override
    public PageUtils queryPage(Map<String, Object> params) {
        IPage<CategoryEntity> page = this.page(
                new Query<CategoryEntity>().getPage(params),
                new QueryWrapper<CategoryEntity>()
        );

        return new PageUtils(page);
    }


    @Override
    public List<CategoryEntity> listWithTree() {
        //1.查出所有的分类
        List<CategoryEntity> entities = baseMapper.selectList(null);
        //2.组装成父子的树结构
        List<CategoryEntity> level1Menus = entities.stream()
                .filter(categoryEntity ->
                            categoryEntity.getParentCid().longValue() == 0)
                .map( (menu) ->{
                    menu.setChildren(getChildrens(menu,entities));
                    return menu;
                })
                .sorted( (menu1, menu2) -> {
                    return (menu1.getSort() == null ? 0 : menu1.getSort()) -
                            (menu2.getSort() == null ? 0 : menu2.getSort());
                })
                .collect(Collectors.toList());
        return level1Menus;
    }



    //递归查找所有菜单的子菜单
    private List<CategoryEntity> getChildrens(CategoryEntity root,List<CategoryEntity> all){
        List<CategoryEntity> childrens = all.stream()
                .filter(item ->{
                    return item.getParentCid() == root.getCatId();
                })
                .map(item ->{
                    item.setChildren(getChildrens(item,all));
                    return item;
                })
                .sorted( (menu1, menu2) -> {
                    return (menu1.getSort() == null ? 0 : menu1.getSort()) -
                            (menu2.getSort() == null ? 0 : menu2.getSort());
                })
                .collect(Collectors.toList());
        return childrens;
    }

    @Override
    public void removeMenuByIds(List<Long> asList) {
        //TODO 1.检查当前的菜单是否被引用
        baseMapper.deleteBatchIds(asList);
    }

    @Override
    public Long[] findCateLogPath(Long catelogId) {
        List<Long> paths = new ArrayList<>();
        paths = findParentPath(catelogId, paths);
        //收集的时候时顺序，前端时逆序显示，所以用集合共计给他逆序以下
        Collections.reverse(paths);
        return paths.toArray(new Long[paths.size()]);
    }

    @Override
    public void updateCascade(CategoryEntity category) {
        this.updateById(category);
        categoryBrandRelationService.updateCategory(category.getCatId(),category.getName());
    }

    /**
     * 递归收集所有父节点
     * @param catelogId
     * @param paths
     * @return
     */
    private List<Long> findParentPath(Long catelogId, List<Long> paths) {
        //1.收集当前系欸但id
        paths.add(catelogId);
        CategoryEntity byId = this.getById(catelogId);
        if(byId.getParentCid() != 0){
            findParentPath(byId.getParentCid(), paths);
        }
        return paths;
    }

}